Method of and apparatus for wrapping strand material around alpha core



pr H. F. CART-ER METHOD OF AND APPARATUS FOR WRAPPING STRANDMATERIAL-AROUND A CORE .Filed Dec. e, 1923 3 Sheets-Sheet l 67 .j A IE..

April 2m 192'?.

H. F. CARTER METHOD OF AND APPARATUS FOR WRAPPING STRAND MATERIAL AROUNDA CORE Filed Deo. 6. 1,923

5 Sheets-Sheet 2 AWN zu N92?? 1,625,983

H. F. CARTER f METHOD 0F AND APPARATUS FOR WRAPPING `STRAND MATERIALAROUND A CORE Filed Deo. 6. 1923 3 Sheets-Sheet y/156ml /Z' Caffe/'JLA12 ynmm Patented Apr. `26, .1927

UNITED STATES PATENT OFFICE.

HERBERT FRED CARTER, OF CICERO, ILLINOIS, 'ASSIGNOR TO WESTERN ELECTRICCJOMIEANY,` INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

METHOD OF AANI! APPARATUS FOR WRAIIPING STRAND MATERIAL AROUND A CORE.

Application iled'December 6, 1923. Serial No. 678,982.

This invention relates to improvements in a method of and apparatus forWrappmg strand material around aI core,- and more particularly to amachine for applying ribbon or tape spirally to a continuous core.

One manner of increasing the inductance oi' a conductor employed for thetransmission ot alternating current is 'to wrap the conductor spirallywith a layer of Wire or tape of magnetic materia-l. This method is knownin the art as continuous inductive loading as distinguished from lumploading by means of coils distributed along the conductor. Untilrecently iron has been considered to be the only material available forcontinuous loading. It has been discovered, however, that a moresuitablematerial may be produced inthe form of an alloy of nickel and iron.`When these -two'metals are `in proper proportions andthe alloy is givenproper heat treatment, a material having very high permeability at lowmagnetizing forces is obtained. For a full disclosure of themetallurgical and electrical characteristics of this alloy and itsl heattreatment, reference is -made to the co-pending applications of GustaveWV. Elmen, Serial No. 477,- 877, filed May 31, 1921; Oliver E. Buckley,Serial No. 492,7 25, filed August 16, 1921, and Gustave W. Elmen, SerialNo. 557,928, filed May 2, 1922.

One method of applying the alloy loading material above described to acomposite signalling conductor is that described in a Patent'#1,537,575, issued May 12, 1925, toA. F. Bandar, in which the loadingmaterial is applied in the form of tape lWrapped around the conductorand subjected to the requigite heat treatment While Wrapped thereon.

It has been found that when this alloy loading material is subjected tostresses or strains the permeability thereof is materially lowered andthat in some cases these deleterious' stresses and strains occur duringthe heat treatment of theloading material and are due to theconstruction. of the composite conductor and also to the manner ofWrapping-the loading-material thereon.4

The primary object of this invention is to provide a method of andmechanism for wrapping the magnetic material around the compositeconductor in such 'manner that the magnetlc material' will not besubjected to any deleterious stresses or strains during the heattreatment thereof. To this end a method and mechanism are provided forwrapping the magnetic loading material around the composite conductorWith a certain degree of looseness, the loading material being subjectedto a minimum amount of bending, a low degree of tension, and to thecomposite conductor, the `purpose of;VV

which Will be hereinafter explained.

Other objectsjand advantages of the in` vention Will more fully appearfrom the following description and Will be particularly pointed out inthe appended claims.

Although the method and apparatus herein disclosed are particularlyadapted for the manufacture of continuously loadedsignallingqconductors, it is to be understood that they may be used forvarious other purposes Without departing'from the spirit and scope of'the invention.

In the accompanying drawings,

Fig. 1 is a side elevation of taping head made in accordance with theinvention;

Fig. 2 is an enlarged sectional detail view showing the roller device ornozzle for supporting the core and to` insure its traveling in astraight line at the point of application of the tape thereto;

Fig. 3 is a vertical sectional view vtaken on the line 3-3of Fig. 2;

Fig. 4 is an enlarged view showing the guiding rollers for centering thecomposite conductor Within the nozzleand also showing the manner inwhich the said# rollers loosen the copper tapes of thecompositefcondu'ctor at the point where the magnetic loading material isWrappedv th erearound;

fragmentary detaii on the line 6 6 of Fig. 2 and looking in thedirection of the arrows;

Fig. 7 is an enlarged fragmentary vert1cal sectional view of a loadedsignalling conductor in which the loading material has lli been appliedby the improved form of taping head' V Fig. 8 is an enlarged sectionalview taken on the line 8 8 of Fig. 3 looking in the direction indicatedby the arrows, showing the latch means for holding the nozzle rollersaway from the core and illustrating the said means in an operatedposition; land Fig. 9 is an enlarged sectional view taken on the line 99 of Fig. 3 and showing the guide for the tape. 2

The drawings illustrate an apparatus by which the method may bepracticed. This apparatus comprises essentially an improved form oftaping head which may be applied to the taping machine fully disclosedin the patent to F. S. Kochendorfer et al., No. 1,565,652, issuedDecember 15, 1925, in place of the taping head herein illustrated, andfor this reason only the improved' form of taping head is disclosed inthis application, reference being made to the above mentioned patent fora full disclosure of a machine to which it may be applied.

It is believed that the method will be read- Y ily understood by adescription lof an apparatus by which it may be performed, whichcompri-ses a taping head consisting of a disk 10 which is secured bymeans of a'key 11 to a hollow shaft 12 (Fig. 1) which is suitablyconnected to the main driving shaft of the taping machine (not shown).In front of the disk 10 and rotatable upon a ball bearing 13 carried bythe shaft 12 is a. tape pad carrier 14 provided with a plurality ofopenings 15 in its face for lightening it. The rear face of the carrier14 is provided with an annular shaped ridge 16 supporting a frictionring 17, the face of the latter being wider than that of the ridge 16and extending toward the axis of the head (Fig. 1). A second ring 18 ismounted adjacent the ring 17 and is supported by` a metallic ring 19carried by screws 2O mounted in the disk 10.

The tension between the friction rings 17 and 18 may be regulated byadjusting the screws 20, three of which are provided spaced 120D apart.The screws 20 pass through shouldered openings 21 in the disk 10 and arescrew-threaded into the ring 19. Compression springs 22 positionedaround the screws 20 and between a shoulder 23 formed thereon and alshoulder formed in the opening 21 function to provide a constant tensionbetween the friction rings 17 and 18 at all times. Any wear on kthefriction surfaces of the rings is taken up by the springs A22. Thescrews 20 are held in their set posi- Three pins 26 spaced 120 apart aremounted on the disk 10 (Fig. 5) and project into suitable openingsprovided in the supporting ring 19 midway between the screws 2O and atequal distances from' the aXisof the head. The pins 26 form the`drivingconnection between the disk 10 and the supporting ring 19, therebytaking all strain oif the adjusting screws 20.

'Means .for supplying a uniform andV sensitive tension to the tape padcarrier 14 (to which a holder supporting the tape is attached,hereinafter to be described) in such a manner that it will readilyrespond to changes in the speed of the serving head, as when starting orstopping and thereby tending to prevent the breaking of the tape beingserved, will now be described.

Secured to a shoulder formed on the carrier 14 is a ring 27 of anysuitable material forming a brake drum and engaging therewith is aflexible brake. band 28 suitably secured at one end to a pin 29 1 and 5)secured in the disk 10 and at its other end to the short arm of acentrifugally operated lever 30 pivotally secured to the disk 10 at apoint 31 diametrically opposite the pin 29. Upon a screw-threadedrightangle extension 32 of the'long arm of the lever 3U is threaded a weight33 adapted to be held in a set position, after being adjusted, by a locknut 34. A tension sp1-ing 35 with one vend secured to thevdisk 10v andits other end to the long arm of the lever 30 functions to hold thebrake band 28 with a certain degree of tension against the brake drum 2Twhen the serving head is stationary and acts to resist the action ofcentrifugal force to throw the weighted end ofthe lever' 30 outward whenthe head is revolving. With proper adjustment the brake band isautomatically released from -the brake drum just before the head reachesmaximum speed. A stop pin 36 .prevents the lever 30 from turning aboutits pivot 31 further than is necessary afterthe brake band has beenreleased.

In the operation of the serving head the braking force between the brakeband 28 and the brake drum 27 on the carrier 14 decreases as the speedof the winding head increases, due to the action of centrifugal force,the braking force being greatest when the head is traveling at itsminimum speed.

The end of the shaft 12 projectsoutside screws 50.

by a left-hand thread indicated at 41 to prevent it from turning loosewhen the serving head revolves, which movement is in a righthanddirection. A roller bracket carrier 42 is rotatably mounted upon thehousing 40 between a flange 43 thereon and a cover 44 secured to thehousing 40 by screws 45. Three pins 46, 46 (Figs. 2 and 3) 120 apart andeach pivotally supporting a roller bracket 47 carrying a roller 48, aresupported at one end in the housing 40 and at their other end in thecover`44. 'Between'the carrier 42 and the cover 44 is a cover member 49in the form` of a ring secured to the carrier 42 by The roller bracket47 is pivoted intermediate its lengthand to one side of a linedrawnbetween its ends, the inside end carrying the roller 48 and theoutside end equipped with a pin 51 projecting Pat each side into slots52 (Figs. 2 and 3) formed in the carrier 42 and its cover 49.

Each of the rollers 48 is spool shape-d and comprises a central arbor 53and annular flanges 54 and 55, the flange 55 having a diameter lessthanV the diameterof ,the flange 54 (Figs. 2 and 4), the purpose ot'which will be hereinafter explained.

The surfaces of the covers 49 and 44 which are in sliding engagement(Fig. 2) are'eaeh formed with complementary depressions 56. (Fig. 6)spaced 120 apart. Secured within. each of the pockets formed by thedepressions 56 are two spring holders 57, one se' cured at one end ofthedepression 56 in the cover 49, and the other in -the opposite end ofthe pocket in' the depression 56 of the cover 44.' Mounted between eachpair of holders is a compression spring 58. The roller brackets 47 arenormally held inthe position shown in Fig. 4 wherein the flanges 54 restagainst the composite conductor, while the flanges are positioned aboveand normally out of contact with the loading ape wrapped around thecomposite conducor. v

To release the flanges 54 from their enga ement with the core .asuitable pin or sty us is inserted in an opening 59 provided in thecarrier 42, as indicated in dotted outline in Fig. 2, and thereafter thecarrier is revolved on the housing` 40 clock-wise. Due to the rollerbrackets being pivoted in the ,housing 4() and the pins 51 engaging 'theslots 52 in the carrier 42, the three rollers 48 will be rotatedclockwise about their pivots 46 and away from the core to be taped, whenthe carrier is revolved as described above. The position of the rollersafter being moved is indicated in dotted outline in Fig. 3. A springpressed latch 60 is suitably mounted" in thecarrier 42 (Figs. 31anil 8)and .after moving` the rollers to'the dotted line position, the latchsprings into an opening 61 in the housing 40, thereby holding thecarrier 42l from moving back to its normal position. A

handle 62 is provided on the latch 60 to draw it out ofthe opening 61,and when the latch is free of the `opening the rollers will move backand engage the core due to the action of the springs 58.

Mounted on the housing 40 as shown in Figs. l, 3 and 9 is a tape guide63. The tape guide comprises a plate having an angular slot 64 formedtherein constituting the guiding portion, the plate being secured to thehousing 40 by screws 65. A guide pulley 66 (Figs. l and 5) is mountedupon the face ot" the disk 10 near the periphery thereof and l freelyrotatable upon a stud 67 provided with a face 68 cut on an angle.I Theguide 63 and the pulley 664 function to lead the tape to the core at thedesired angle. stud 67 is secured to the disk 10 by a bolt and nut 69,and by loosening the nut the stud may be turned'with the bolt, therebycausing' the pulley to. guide the tape at a different angle.

A plurality of radially disposed and equally spaced holes 70, 7 O areprovided in the face of the disk 10 for locating the pulley 66 and asecond pulley 7l adjacent. thereto over which the tape is guided beforeit is guided by the pulley 66. Counter weights 72 are mounted on thedisk 1() at points diametrically opposite the pulleys 66 and 71 or atother positions afforded by the openings 7 0 to properly balance theserving head.

s The'guide pulley 66 is so located that the loading tape is fed ontothe core tangentially thereof and in a straight line from the 4therollers 48 away from the core is countei acted to a certain extent bythe circularly arranged springs 58 acting against the outside ends ofthe roller brackets 47 to turn the'm counter-clockwise.

llfl

A tape pad holder 73 (Figs. 1 and 5)l .holding a supply of tape 74 andprovided with a hub 75 tits over a hub-like portion 76 formed on thetape pad carrier14 with the tape between the disk portion on the carrier14 and theY pad holder 7 3. The pad holder is formed with a plurality ofopenings 77, 77, through which the amount of tape on the holder may beobserved while the machine-is stationary or in operation, so that theoperator, at alltimes, may know when thetape supply on the holder isabout to be exhausted. These openings also serve to lighten the holder.-The pad holder 73 is secured to the carrier 14 to turn therewith by akey 78 suitably secured in the hublike portion 7 6 of the carrierentering la keyl Way 79 formed in the hub 75 of the pad holder. The padholder 7 3 forms the subject-matter of Patent No. 1,545,906 to F. SKochendorfer, issued July 14, .1925, reference to which may be had foraL more detailed description thereof.

ln the operation of the machine the conductor to be wrapped with theloading tape 74 is fed from a supply spool (not shown) through thehollow shaft 12 between the flanges 54 of the rollers 48, served withthe magnetic loading material 74. and then taken up on a suitablestorage device (not shown). i

The tension exerted on the tape 74 between 'the guide pulleyl (36 andthe core 100 is determined by the setting of the tension between thefriction rings 17 and 18 by adjusting screws 20. W'here the taping headis used for applying the magnetic loading material of the typeheretofore described. these screws are so set that a tension of twelveounces is exerted on the tape when the tape pad is full, which tensionincreases as the tape pad diminishes in size, reachingl -a maximum oftwenty-four ounces when the tape pad is practically exhausted.

The fianges 54 of the rollers 48 serve to centralize the conductorwithin the nozzleso that the loading tape may be accurately wrappedtherearound. After the loading tape has been applied to the conductor,the taped conductor emerges from the nozzle without being subjected. toany rolling` ac lion` since the flanges 55 of the rollers 4F are spacedtherefrom, 'as shown in Fig. 4, and during the normal operation of thenozzle do not contact with the taped conductor. The flanges 55 merelyconstitute a guiding means for the taped conductor as it emerges fromthe nozzle whenever th#` .said conductor is 4not pulled accuratelythrough the center of the nozzle by the capstan of the taping machine(not shown).

i The loading tape 74 is relatively stiff and springy, and since it isnot bent between the guide pulley 66 and its. cngagei'nent with thecore, is not subjected to any rolling action, and is applied underrelatively light tension (12 to 24 ounces), the helix thereof formed onthe core does not tightly grip the core, but surrounds it with a certaindegree of looseness, as shown in Fig. 7. The actual clearance betweenthe loading tape and the core is very small (approxiq mately half athousandth of an inch) which appears as an appreciable distance in Fig.7 since this figure is a very considerable enlargement of the actualloaded conductor.

Asmshown in the drawings, the core 100 comprisesca composite" conductorconsisting of a central metallic wire 101, preferably of.

copper, around which a plurality of copper tapes 102 are tightlystranded. The loading tape 74 is fed to the core 100 in a direction suchthat it is Wrapped around the composite conductor in a directionopposite to that in which the copperl tapes 102 are 'stranded around thecentral Wire 101, Vas

shown in Figs. 2 and 4. The flanges 54 of the rollers 48 are forced intocontact with the core under considerable pressure exerted by the springs58 and these flanges in addition to centralizinv' the core within thenozzle also serve to twist the copper V'tapes 102 around the centralwire 101 due to the rotation of the flanges therearound, .which twistingaction is in the same direction -in which the tapes 102 are strandedaround the central wire 101. 'The twisting action of the flanges 54serves to tighten on the central wire 101 the section of the tape 102between the flanges 54 and the core supply reel (not shown) and servesto loosen the' section of these tapes between the flanges. 54 and thepoint ef application of the' .magnetic loading material 74 thereon, asis readily underf stood. As a consequence, just prior to theyapplication of the magnetic loading material, .the copper tapes 102 areloosened slightly from the central wire 101, as shown in Fig. 7.

The rollers 48 function to wrap 'the alloy tape 74 around the conductor101 .in such manner that the alloy tape will not be subjected todeleterious stresses and strains during the heat treatment thereof. -Theex planation of this result is believed to be as follows:

The central copper conductor 101 and the copper tapes have a highercoefficientl of elongation than the magnetic loading tape 74. Measuringa plurality of samples of the composite conductor and the alloy tape,the

former has been found to have 'a coefficient drawn into close Contactwith the copper l conductor and may be subjected to deleterions stressesand strains which will result in a decrease ofthe permeability of theload. ing material. Where.. theieomposite conductor is wrapped with theloading tape by the mechanism heretofore described, a space is providedbetween the alloy tape and the loading material sufficient to preventthe alloy tape upon cooling to be drawn into such intimate contact withthe composite conductor as to be subjected to deleterious Theadvantageous results due' to the use.

of the rollers 48 may further be explained somewhat as follows:

The copper tapes 102 upon being stranded around the central conductor101 do not present a true cylindrical surface since the edges of thetape do not liein close contact with the central conductor` but presentspiralled edges. During the cooling portion o i the heat treatment, thealloy tape cools more y ly comes into intimate-contact -with the raisededgesl ofthe copper tapes. As the cooling proceeds, a sticking orwelding of the materials yoccurs at various points along these edges andthe subsequent contraction of the copper therefore sets up stresses inthe alloy tape. However, when the alloy tape is applied by the mechanismand in the manner heretofore described the space between the loadingtape 74 and the copper tapes 102, afforded by the loose wrapping of theloading tape on the composite conductor, permits free relativemovementbetween the alloy loading tape 7 4 and the copper tapes 'durinthe heating and cooling thereof incident 1n the heat treatment of theloading material and prevents the latter from being subjected todeleterious stresses and strains.

What is claimed is:

1. In a mechanism for serving strand material spirally to a core, arotatable serving head, a strand material supply'holder carried bytheserving head, a serving device rotatable with sai-d head, means carriedby said serving device so located as to be out of contact with theserved strand material and adapted to support the core to insure itstraveling in a, straight line at the point of application of thestrandserving material, and means for subjecting said means topressuretangentially of the served strand.

2. In a mechanism for serving tape spirally to a core, a rotatableserving head, a tape supply holder carried by the said head, a servingvdevice rotatable with said head,

i and a plurality of rollers carried by said serving device, saidrollers so located as to be out of contact with the served tape and tosupport the core to insure,k its traveling in a straight line at thepoint ofiapplication of the tape.

3. In a mechanism for serving strand ma'- terial spirally to a core, arotatable serving head, a strand material supply holder carried by saidserving head, a serving device rotatable with said head, guide meanscarried by the head over kwhich the strand is guided from t-he ,strandholder to the serving device, said serving device said guidemeans sovpositioned that the strand serving material travels in substantiallystraight lines from the material supply holder to its point of contactwith the core.

so designed. and v 4. In a mechanism for serving tape spiguide meanscarried by they head overgwhich f thetape is guided from the supplyholder lto said servingdevice, said serving device so designed and saidguide means so positioned that the tape travels in substantiallystraight-lines from the tape supply holder to its point of contact withthe core.

5. In a mechanism for serving strand material spirally to a, core, arotatable serving head, a strand material supply holder carried by saidhead, a serving device rotatable with said head, a guide roller carriedby the head over which .the strand material is guided from the supplyholder to said servlng device, said serving 'device 'so designed andsaid guide roller so positioned that the strand material is provided a`straight and uninterrupted path from the guide roller to its point ofcontact with the core.

6. In a mechanism for serving tape spirally to a core, a rotatableserving head, a tape supply holder carried by said head, a servingdevice rotatable with said head, guide means carried by the head overwhich the tape is guided from the supply holder to said serving device,said serving device so designed and said guide means so positioned thatthe tape is provided a straight path from the guide means to its pointof contact with the core, and means carried by vsaid serving device andso located as to be out of contact with the .taped ;ore and adapted tosupport the core to insure its traveling in a. straight line at the 5point of application of the tape.

7. In a mechanismy for serving tape spi-- rally toa core, a rotatablehead, a tape supply holder carried by said head, a serving devicerotatable with said head, a guide roller carried by the head over whichthe tape is guided from the supply holder to` saidserving device, saidserving` .device so designed'and said guide roller so positioned thatthe tape is provided a straight and uninterrupted path from the guideroller to its Ypoint offcontact with the core, and a roller carried bysaid serving device and so located as to be out of contact with thetaped core and to support the core to insure its traveling in a straightline at the point of application of the tape.

-8. In a mechanism for serving tape spirally toa core, a rotatableservlng head, a

tape supply holder carried'by said head, a

serving device rotatable with said head, a

roller carried by said serving device, a. flange associated with saidroller engaging the core at a point in advance of the application of thetape thereto and in such manneras to support the core and insure itstraveling in a straight line at the point of application of the tape. Y

9. In a mechanism for serving tape spirally to a core, a rotatableserving head, a tape supply holder carried by said head, a servingdevice rotatable with said head. a roller carried by said servingdevice, a flange having a greater diameter than a second flangeassociated therewith, the said roller so located within the servingdevice that the larger flanges thereof engage theeore at a pointin'adyance of the application ot' the tape thereto and in such manner asto support the core and insure its traveling in a straight line at thepoint of application of the tape, the smaller diameter flangesassociated with said rollers being positioned above the taped portion ofthe core but normally out of contact therewith.

10. In a mechanism for serving metallic tape on a metallic core, arotatable serving head, a tape supply holder carried thereby androtatable therewith in such manner that the tape is wrapped onthe corewith a minimum amount of tension exerted onthe tape. and means carriedby the serving head and so. located as to be out of contactr with theserved tape to support the core to insure its traveling in a straightline at the point of application of the tape.

11. In a mechanism for serving metallic tape on a metallic core, arotatable serving head, a supply of tape carried thereby and rotatabletherewith in such manner that the tape is wrapped on the core with aminimum amount of tension exerted on the tape, and a spring pressedroller rotatable with said serving head, a flange larger than saidroller engaging the core at a point in advance of the application of thetape thereto to support the core and insure its traveling in a straightline' at the point of application of the tape.

12. In a mechanism for serving metallic tape on a metallic core, arotatable serving head, a supply of tape carried thereby and rotatabletherewith in such ymanner that the tape is wrapped on the core with aminimum amount of tension exerted on the tape, guide means for the tapecarried by the serving head, said serving means so designed and theguide means so positioned that the tape is provided a straight path fromthe guide means to its point of contact with the core, and meansengaging the core and out ot contact with the taped portion thereof,said means supporting the core to insure its traveling in a straightline at the point of application of the tape.

13. In a mechanism for serving metallic tape on a metallic core, arotatable serving head, a supply ot' tape carried thereby" and rotatabletherewith in such manner that the tape is wrapped on the core with aminieling in a straight line at the point of application of the tape.

14. In a mechanism for serving strand ma- 4 terial spirally to a core,which'consists of a central strand and a wrapping of vstrand materialthereon, a rotatable serving head, a stra-nd material supply holdercarried by said head, a serving device rotatable with` said head, andmeans associated with said serving device and in contact with thecomposite core for loosening the strand wrapping thereon ata point inadvance of the application of the strand serving material to saidcomposite core.y

15. In a mechanism for serving strand material spirally to a core, whichconsists of a central strand and a wrapping of strand material thereon,a rotatable serving head, a strand material supply holder carried ,bysaid head, a serving device rotatable with said head, and meansassociated with said serving device and in contact with the compositecore to support ther core to insure its travelingin a straight line atthe point of application of the tape, said means designed to loosen thestrand wrapping of the composite core at a point prior to theapplication of the strand serving material thereto.

16., In a mechanism for serving tape spirally to a composite core,consisting of a central strand and a wrapping of strand materialthereon, a rotatable serving head. a tape supply holder' carried by thesaid head, a serving device rotatable with said head, and meansassociated with said serving device and inengagement with the core toinsure its traveling in a straight line at the point of application ofthe tape, said means designed to loosen the strand wrapping of the.composite core at a point in advance of the application of the servingtape thereto.

17. In a mechanism for lserving tape.

spirally to a 'composite core, consisting of a central strand and awrapping of strand' material thereon. a rotatable serving head, a tapesupply holder carried by said head.

a serving device rotatable with said head,

on, a rotatablelserving head, a ltape supply,

holder carried by said head, a serving device rotatable with said head,a pluralityv ot' rollers associated with said serving de vice and solocated as t0 be in contact With the composite core, said rollersadapted to loosen the strand Wrapping of the core at a point in advanceof the application of the tape serving thereto.

19. In ,a mechanism for serving tape spirally to a composite core,consisting of a central strand and a strand Wrapping thereon, arotatable serving head, a tape supply holder carried by said head, aserving device rotatable with said head, a plurality oi. rollersassociated With said serving device and in Contact with the compositecore to support the core to insure its traveling in a straight line atthe point of application ot the tape, said rollers adapted to loosen thestrand Wrapping of the composite core of the point of application of theserving tape thereto.

20. In a mechanism for serving 'tape spirally to a composite core,consisting of a central strand and a strand Wrapping thereon. arotatable serving head, a tape supply holder 'carried by said head, aserving device rotatable with said head, a plurality ot rollers carriedby said serving device` so located as Ato be in contact With thecomposite core and out of contact with the served tape, said rollersserving to support the core to insure its traveling in a straight lineat the point ot application of the tape so positioned that the'strandserving material is provided with a straight path from the guiding meansto its point of contact with the core.

23; In a mechanism. for serving tape spirally to a core, arotatablesem-'ing head, a tape supply holder carried by said head, aserving device rotatable With said head, a plurality ofspool shapedrollers carried by said serving device. said rollers so located that oneflange thereof engages, the core at a point in advance of theapplication of tape thereto and in such manner as to support the coreand insure its traveling in a straight line at the` point of applicationof the tape, and means 'for pressing said rollers tangentially againstsaid served-strand.

24. In a mechanism for serving 'tape to a core, a rotatable servinghead. a tape supply holder associated therewith, a serving devicerotatable with the head, a roller carried by said device', a supporttherefor, a flange associated with said roller engaging vthe core at apoint in advance ot' the point and to loosen the strand wrapping ofthecomposite core at the point of application of the serving tapethereto. Y

21. The method of serving strand material to a conductor, which consistsin subjecting the conductor ,to pressure, serving the material to theconductor synchronously witln its subjection to pressure, and guidingthe material from its supply source to its point of contact with theconductor in substantially straight lines. y

22. In a mechanism for serving strand material spirally to a core, arotatable serving head, a strand material supply holder carried by saidserving head, a serving device rotatable with said head, freelyrevolvable guide means carried b v the head over which the strand isguided from the strand holder to the serving head, said serving deviceso designed, and said guide means ot application ot' the tape theretoand in such'manner as to support the core and 1nsure its traveling` inastraight line'at the 4point of application of the tape, and means formoving tliesaid support to vary the position of said roller with respectto the core.-

25. Ina mechanism 'for serving tape spirally to a core, a rotatablehead, a tape supply holder earried by said head, a serving devicerotatable with said head, a guide rolleru carried by the head over whichthe tape is guided from the supply holder to said serving device, saidserving device so designed and said guide roller so positioned that thetape is provided a straight and uninterrupted path rom the guide rollerto its point ot contact With the core, and a plurality of rollerscarried by said serving devices and so located as to be out of contactwith the taped core and to support the core to insure its traveling in astraight line at the point of application of the tape, and means forswinging said rollers into or out of engagen'ient With said core.

26. In a machine for applying-tape material t'o an elongated core, meansfor apply ing mechanical force to an element ot said core whereby thecircumference of a portion of said core is increased, means for applyingthe tape about said portion. and means for advancing said core to removesaidvportion from the influence of said force.

27. The method ot applying a serving to a core which comprises applyingthe serving to said core While said core is in a non-compact condition,and subsequently increasing by the application of mechani lal force thecompactness ot said core to secure looseness ot said serving.

l28. A. method of applying a loose Wrapping about av stranded core whichcomprises temporarily loosening the strands'of said core, Wrapping atape about said strands 1n their loosened condition, and then allowing`said tape to assume a loosened condition.

29. A method of prmiding a stranded core with a loose wrappingcomprising partially separating the strands ol said eore, wrapping atape about said separated strands, andthen causing said strands to beless separated.

30. The method of producing a composite core surrounded by a strandwhich includes the steps of serving the strand about the composite coreand applying a twisting force to said core sulioient to secure loosenessof said strand about said core.

3l. A method of securing looseness ot' a wrapping about a stranded coreveolnprisiin,r applying a ineehanieal force to an element ot saidstranded core in order to increase the eircunilerence,of a portion ofsaid stranded core, then \\'ra}:i ping atape about said portion, andrelievinzgr said portion from the influence of said force.

In Witness whereof, I hereunto subscribe in y nanie this 14th day ofNovember, A. D.

'HERBERT FRED CAR-TER.

